<template>
  <div class="shopcart">
    <div class="content" @click="toggleList">
      <div class="content-left">
        <div class="logo-wrapper">
          <div class="logo" :class="{'highlight':totalCount>0}">
            <span class="icon-shopping_cart" :class="{'highlight':totalCount>0}"></span>
          </div>
          <div class="num" v-show="totalCount>0">{{totalCount}}</div>
        </div>
        <div class="price" :class="{'highlight':totalPrice>0}">￥{{totalPrice}}元</div>
        <div class="desc">另需配送费￥{{deliveryPrice}}元</div>
      </div>
      <div class="content-right">
        <div class="pay" :class="payClass">{{payDesc}}</div>
      </div>
    </div>
    <div class="ball-container">
      <div v-for="ball in balls">
        <transition name="drop" @before-enter="beforeDrop" @enter="dropping" @after-enter="afterDrop">
          <div class="ball" v-show="ball.show">
            <div class="inner inner-hook"></div>
          </div>
        </transition>
      </div>
    </div>
    <transition name="fold">
        <div class="shopcart-list" v-show="listShow">
          <div class="list-header">
            <h1 class="title">购物车</h1>
            <span class="empty" @click="empty">清空</span>
          </div>
          <div class="list-content" ref="listContent">
            <ul>
              <li class="food" v-for="food in selectFoods">
                <span class="name">{{food.name}}</span>
                <div class="price">
                  <span>￥{{food.price*food.count}}</span>
                </div>
                <div class="cartcontrol-wrapper">
                  <cartcontrol @add="addFood" :food="food"></cartcontrol>
                </div>
              </li>
            </ul>
          </div>
        </div>
      </transition>
  </div>
</template>

<script type="text/ecmascript-6">
import BScroll from 'better-scroll';
import cartcontrol from '../cartcontrol/cartcontrol';

  export default {
    props:{
      selectFoods:{
        type:Array,
        default(){
          return [];
        }
      },
      deliveryPrice:{
        type:Number,
        default:0
      },
      minPrice:{
        type:Number,
        default:0
      }
    },

    data(){
      return{
        balls:[
          {
            show:false
          },
          {
            show:false
          },
          {
            show:false
          },
          {
            show:false
          },
          {
            show:false
          },
        ],
        dropBalls: [],
        fold: true
      }
    },

    computed:{
      totalPrice() {
        let total = 0;
        this.selectFoods.forEach((food)=>{
          total += food.price * food.count;
        });
        return total;
      },
      totalCount() {
        let count = 0;
        this.selectFoods.forEach((food)=>{
            count += food.count;
        });
        return count;
      },
      payDesc() {
        if(this.totalPrice === 0){
          return `¥${this.minPrice}元起送`; 
        }else if(this.totalPrice<this.minPrice){
          let diff = this.minPrice - this.totalPrice;
          return `还差¥${diff}元起送`
        }else{
          return '去结算';
        }
      },
      payClass() {
        if(this.totalPrice< this.minPrice){
          return 'not-enough';
        }else{
          return 'enough';
        }
      },
       listShow() {
        if (!this.totalCount) {
          this.fold = true;
          return false;
        }
        let show = !this.fold;
        if (show) {
          this.$nextTick(() => {
            if (!this.scroll) {
              this.scroll = new BScroll(this.$refs.listContent, {
                click: true
              });
            } else {
              this.scroll.refresh();
            }
          });
        }
        return show;
      }
    },

    methods: {
      addFood(target) {
        this.drop(target);
      },
      toggleList() {
        if(!this.totalCount){
          return;
        }
        this.fold = !this.fold;
      },
      hideList() {
        this.fold = true;
      },
      empty() {
        this.selectFoods.forEach((food) => {
          food.count = 0;
        });
      },
      pay() {
        if (this.totalPrice < this.minPrice) {
          return;
        }
        window.alert(`支付${this.totalPrice}元`);
      },
      addFood(target) {
        this.drop(target);
      },

      drop(el) {
        for (let i = 0; i < this.balls.length; i++) {
          let ball = this.balls[i];
          if (!ball.show) {
            ball.show = true;
            ball.el = el;
            this.dropBalls.push(ball);
            return;
          }
        }
      },
      beforeDrop(el) {
        let count = this.balls.length;
        while (count--) {
          let ball = this.balls[count];
          if (ball.show) {
            let rect = ball.el.getBoundingClientRect();
            let x = rect.left - 32;
            let y = -(window.innerHeight - rect.top - 22);
            el.style.display = '';
            el.style.webkitTransform = `translate3d(0,${y}px,0)`;
            el.style.transform = `translate3d(0,${y}px,0)`;
            let inner = el.getElementsByClassName('inner-hook')[0];
            inner.style.webkitTransform = `translate3d(${x}px,0,0)`;
            inner.style.transform = `translate3d(${x}px,0,0)`;
          }
        }
      },
      dropping(el, done) {
        let rf = el.offsetHeight;
        this.$nextTick(() => {
          el.style.webkitTransform = 'translate3d(0,0,0)';
          el.style.transform = 'translate3d(0,0,0)';
          let inner = el.getElementsByClassName('inner-hook')[0];
          inner.style.webkitTransform = 'translate3d(0,0,0)';
          inner.style.transform = 'translate3d(0,0,0)';
          el.addEventListener('transitionend', done);
        });
      },
      afterDrop(el) {
        let ball = this.dropBalls.shift();
        if (ball) {
          ball.show = false;
          el.style.display = 'none';
        }
      }
    },
    components:{
      cartcontrol
    }
  }
</script>

<style lang="stylus" rel="stylesheet/stylus">

  @import "../../common/stylus/mixin.styl";

  .shopcart
    position fixed
    left 0
    bottom 0
    z-index 50
    width 100%
    height 48px
    background #000
    .content
      display flex
      background #141d27
      font-size 0
      color rgba(255,255,255,0.4)
      .content-left
        flex 1
        .logo-wrapper
          display inline-block
          vertical-align top
          position relative
          top -10px
          margin 0 12px
          padding 6px
          width 56px
          height 56px
          box-sizing border-box
          border-radius 50%
          background #141d27
          .logo
            width 100%
            height 100%
            border-radius 50%
            text-align center
            background #2b343c
            &.highlight
              background rgb(0,160,220)
            .icon-shopping_cart
              line-height 44px
              font-size 24px
              color #80858a
              &.highlight
                color #ffffff
          .num
            position absolute
            top 0
            right 0
            width 24px
            height 16px
            line-height 16px
            text-align center
            border-radius 16px
            font-size 9px
            font-weight 700
            color #ffffff
            background rgb(240,20,20)
            box-shadow 0px 4px 8px 0 rgba(0,0,0,0.4)
        .price
          display inline-block
          vertical-align top 
          margin-top 12px
          line-height 24px
          padding-right 12px
          box-sizing border-box
          border-right 1px solid rgba(255,255,255,0.1)
          font-size 16px
          font-weight 700
          &.highlight
            color #fff
        .desc
          display inline-block
          vertical-align top
          margin 12px 0 0 12px
          line-height 24px
          font-size 10px
      .content-right 
        flex 0 0 105px
        width 105px
        .pay
          height 48px
          line-height 48px
          text-align center
          font-size 12px
          font-weight 700
          background #2b333b
          &.not-enough
            background #2b333b 
          &.enough
            background #00b43c
            color #fff
    .ball-container
      .ball
        position fixed
        left 32px
        bottom 22px
        z-index 200
        &.drop-transition
          transition: all 0.4s cubic-bezier(0.49, -0.29, 0.75, 0.41)
          .inner
            width 16px
            height 16px
            border-radius 50%
            background rgb(0,160,220)
            tarnsition all 0.4s

    .shopcart-list
      position: absolute
      left: 0
      top: 0
      z-index: -1
      width: 100%
      transform: translate3d(0, -100%, 0)
      &.fold-enter-active, &.fold-leave-active
        transition: all 0.5s
      &.fold-enter, &.fold-leave-active
        transform: translate3d(0, 0, 0)
      .list-header
        height: 40px
        line-height: 40px
        padding: 0 18px
        background: #f3f5f7
        border-bottom: 1px solid rgba(7, 17, 27, 0.1)
        .title
          float: left
          font-size: 14px
          color: rgb(7, 17, 27)
        .empty
          float: right
          font-size: 12px
          color: rgb(0, 160, 220)
      .list-content
        padding: 0 18px
        max-height: 217px
        overflow: hidden
        background: #fff
        .food
          position: relative
          padding: 12px 0
          box-sizing: border-box
          border-1px(rgba(7, 17, 27, 0.1))
          .name
            line-height: 24px
            font-size: 14px
            color: rgb(7, 17, 27)
          .price
            position: absolute
            right: 90px
            bottom: 12px
            line-height: 24px
            font-size: 14px
            font-weight: 700
            color: rgb(240, 20, 20)
          .cartcontrol-wrapper
            position: absolute
            right: 0
            bottom: 6px
    // .list-mask
    //   position: fixed
    //   top: 0
    //   left: 0
    //   width: 100%
    //   height: 100%
    //   z-index: 40
    //   backdrop-filter: blur(10px)
    //   opacity: 1
    //   background: rgba(7, 17, 27, 0.6)
    //   &.fade-enter-active, &.fade-leave-active
    //     transition: all 0.5s
    //   &.fade-enter, &.fade-leave-active
    //     opacity: 0
    //     background: rgba(7, 17, 27, 0)
</style>
